Method of after-treating viscose threads advancing in a helical path



Sept. 15, 1953 K. M. M LELLAN 2,552,311

METHOD OF AFTER-TREATING VISCOSE THREADS ADVANCING IN A HELICAL PATH Filed April 20, 1951 2 Sheets-Sheet l INVENTOR KENNETH M. MCLELLAN ATTORNEY Sept. 15, 1953 K. M. M LELLAN 2,652,311

METHOD OF AFTER-TREATING VISCOSE THREADS ADVANCING IN A HELICAL PATH Filed April 20, 1951 2 Sheets-Sheet 2 INVENTOR KENNETH M. MGLELLAN UZZ A/% 4! ATTOSZEY Patented Sept. 15 1953 METHOD OF AFTER-TREATING VISCOSE THREADS ADVANCING IN A HELICAL PATH Kenneth M. McLellan,

to Industrial Rayon Ohio, a corporation of Cleveland, Ohio, assignor Corporation, Cleveland,

Delaware Application April 20, 1951, Serial No. 222,009

4 Claims.

This invention relates to the treatment of filamentary material such as yarn, thread and the like (hereinafter referred to as thread) at elevated temperatures while such thread is continuously stored and advanced on a thread-advancing, thread-storage device in a plurality of generally helical turns. More particularly, it relates to the treatment of thread such as viscose rayon thread with aqueous fluids at elevated temperatures to assist the regeneration and processing of such thread.

In general, a chemical or physical treatment of thread is more thorough and more efficient if it is performed at an elevated temperature. is particularly true, for example, in the manufacture of viscose rayon thread, and especially in the continuous processing systems where a series of coordinated thread regeneration steps are performed on a series of thread-storage, thread-advancing devices. Among the regeneration steps involved are, for example, treatments with aqueous acid solutions, aqueous desulfurizing solutions, aqueous bleaching solutions, and washing treatments with water between any two or more of the chemical treatments mentioned. One or more of the individual treatment steps mentioned may be performed on each of the thread-advancing devices.

The present invention advantageously provides a process whereby the processing time for the regeneration of viscose rayon in a continuous system is materially reduced. In addition, the present invention makes possible a continuous process apparatus which is more simple and smaller in size and cost. In accordance, then, with the present invention this is accomplished generally by temporarily storing and advancing a thread on a thread-storage, thread-advancing device in a plurality of generally helical turns, heating the advancing thread by circulating or passing steam through the interior of the device, and by-passing at least a portion of the steam from theinterior of the device to the exterior thereof, and

I into contact with the advancing thread. Advantageously, at least a portion of the steam employed is condensed and the advancing thread subjected to the action of both the condensate and steam. Condensation of steam may take place within the advancing device or it may take place at the thread-bearing surface thereof, or at both places. Particular advantages, however, derived when a substantial proportion of the condensate is formed within the device and then by-passed, or diverted together with the steam,

to the exterior thread-helix.

The steam condensate or steam, or both, in addition to their function as the source of heat for heating the advancing device and thread thereon also function as thread-washing and leaching media. Moreover, such hot aqueous fluids may also serve to dilute the chemical treating agents that are present on or applied to the actvancing thread. For instance, the advancing thread being contacted by the diverted hot aqueous fluids may already contain one or more oi the chemical treating agents previously mentioned. Such agents may be present on the thread as the result of a prior chemical treatment, or with advantage, such chemical treating agents may be applied to the heated thread-helix and the thread then subjected to the washing or diluting action of the diverted heated fluids. If desired, as illustrated hereinafter in the exam ples, the washing or leaching-out action may be performed by the diverted condensate and steam at a plurality of locations on a single threadhelix, i. e., both before and after an application of a chemical treating agent to such threadhelix. The dilution of chemical treating agents such as sulfuric acid, desulfurizing or bleaching solutions that may be present on or applied to the thread, may be accomplished advantageously by s1ight1y tilting the thread-advancing device so that the condensate-wash liquid is permitted to flow along the thread-helix countercurrently of the advancing thread. i

The emission of steam and water vapor in accordance with the present invention from the exterior surface of the heated thread-advancing device to the atmosphere surrounding the device performs still another very advantageous function. During the regeneration of viscose rayon thread, substantial amounts of salting out takes place on the various mechanical parts and devices such as guides, etc. associated with, or .in the vicinity of, the thread-advancing devices. The aqueous liquids discharged by the thread and by the rotating devices form salt crystals and deposits where they contact such mechanical parts. Such deposits in turn cause breaks inthe running thread. In a process such as that of the present invention where elevated treatment temperatures are employed, there is a greater rate of salt formation due to the higher rate of evaporation of the discharged liquids. By the process of the present invention, however, the steam and water vapor present in the atmosphere surrounding the steam-heated advancing device condense into a mist which settles on and continuously wets out the associated parts referred to, thus avoiding or minimizing the damage caused by the salt deposits.

In practicing the present invention a threadadvancing device is employed having an enclosed. chamber into which the steam is introduced and advantageously circulated prior to diverting desired quantities of the condensate and steam to the exterior to the thread-helix. The chamber walls of the advancing device are provided with circumferentially spaced peripheral openings so that the heated aqueous fluids can flow there through in generally predetermined quantities to selected areas of the reel periphery.

Among the thread-storage, threadadvancing devices that may be employed in accordance with this invention are, generally, any that are adapted to advance thread in general helical turns of thread. Particularly advantageous for the purpose of this invention are the devices on which the traveling yarn describes a helix which is almost circular such as, for example, a threadadvancing reel that operates on the principles disclosed in the Knebusch Patent No. 2,210,914 and in the Corey Patent No. 2,413,217 and of the type illustrated in Figures 2 and 3 of the drawing. In general, this type of thread-advancing reel consists of two reel members each having a periphery of a plurality of longitudinally extending bar members, and each reel member being mounted for rotation on axes that are offset and askew relative to each other. The reel can have an enlarged chamber for condensing steam, or the reel shaft may comprise the condensing area. The chamber is contained in one of the reel members and embodies a fluid tight cylindrical chamber positioned about a hollow reel shaft through which steam is conducted. In the periphery of the cylindrical chamber there are bored a plurality of openings extending to the atmosphere having diameters which permit a predetermined fiow of the heated aqueous fluid, e. g., steam condensate and steam to the periphery of the reel, These passages may be positioned circumferentially at a desired place along the length of the reel so as to provide for one or more hot aqueous fluid treating zones, e. g., hot-water washing or leaching zones, at any desired position along the reel surface. Such positions or zones may be after, before or both before and after, the point of application of a chemical treating agent, 'e. g., acid, desulfurizing, bleaching, etc. solutions.

' This invention will be-more specifically shown and described in the accompanying specification and drawing where-z Figure l is a schematic end view of o'us process rayon spinning machine;

Figure 2 is a cross-section of a thread processing ree1 of this invention; and

Figure 3 is. a further modification in crosssection of a thread processing reel-of this invention.

Referring to Figure l of the drawing there is shown in schematic arrangement a viscose spinning apparatus in which a viscose solution is es:- truded through a spinneret ll into a sulfuric acid coagulating bath Hi to form a rayon thread E2. The thread 12 is withdrawn from the acid bath Ill by a reel l positioned above the bath. The thread may be merely stored thereon while containing entrained acid bath liquor or, if desired, it may be treated with a dilute aqueous acid applied through the distributor tube it. a The thread l2, containing acid, is forwarded by the reel 15 in a downward direction to reel 16 which a continusure within the reel,

4 is heated internally with steam supplied by hol low reel shaft 30.

On this reel the thread is subjected to a washing treatment followed by a dilute aqueous acid treatment to further its regeneration. The washing treatment is performed as follows. A major part of the steam supplied through the hollow reel shaft 30 condenses within the reel and the condensate flows outwardly through peripheral openings 'in the reel to the reel surface, thus subjecting the advancing thread to a condensate-wash treatment. The steam presbecause of the openings, is slightly above 'or nearly atmospheric, thus assisting the steam condensate formed in the reel to flow out to the reel surface together with the uncon'd'ensed steam. The subsequent dilute acid treatment on the heated reel l5 may be accomplished by applying such acid through tube 2i, or a dilute acid condition can be formed on the thread-helix by diluting the acid present .on or entrained by the thread entering the reel .155. The thread l2 discharged from the reel I6 is conducted to reel H which is heated by steam supplied through a hollow reel shaft 3|.

' Reel l! is constructed in a manner similar to reel l6 so as to permit steam and condensate formed within the reel to be diverted to the thread-helix thereon. To the thread-helix on reel ll may be applied a 'desulphurizing solution through tube 22. If desired, prior to such desrilphurizing treatment the thread-helix may be subjected to a condensate-wash treatment by means of condensate diverted from the interior of the reel in a manner similar to reel 15. Further, if desired, the desulp-hurizing treatment may be followed by still another condensatewash treatment on the same reel [1. Thread I2 discharged from reel I1 is conducted to reel. l8 and treated with a mild bleaching solution supplied by delivery tube 24 and the resulting bleachtreated thread then advanced to a wash zone provided by an aqueous washing liquid delivered by tube '25.

Further, if desired, both the de'sulp-hurizing treatment and the bleaching treatment may be performed on thereel I? by applying such chemical agents in sequence through tubes 22 and 23. Further, if desired, an aqueous oil emulsion may be applied to the thread-helix on reel l8 by tube 25 following the bleaching treatment supplied by tube 24. In this manner the oil emulsion from tube 25 may serve the dual function of washing off residual bleach from thethread and also oiling the thread prior to drying on steamheated dryer reel 19;

In contradistinction to the previously described steam heated reels I16 and II; the steam introduced into dryer reel 1'5 through hollow reel t 32 is recycled and the condensate formcdtherein is trapped and also recycled. The oiled and dried thread discharged from reel is is then collected by a cap spinning take-up apparatus as.

In general, the temperature of the heated aqueous fluids, e. g., steam and steam condensate present within the reelor undergoing diversion to the reel surface is in the neighborhood of C. On the other hand, the temperature of the treating liquid and advancing thread on the reel surface may vary depending upon a number of factors such as, for example, the quantity and rate of steam introduced into the reel; the quantity and rate of steam and steam condensate diverted to the thread-helix;the-size andnumber of the orifices employed to divert'the steam and condensate; and the volume and temperature of the treating liquids delivered to the thread-helix. It is found particularly advantageous, however, to adjust and to control such conditions so as to achieve thread treatment temperatures on the reel surface at above about 75 C. and preferably between about 80 and 100 0.

Particular advantages are derived if the factors above mentioned are adjusted and controlled as follows. The steam pressure within the reel may be maintained from about atmospheric pressure to about pounds and preferably at about 1 or 2 pounds. The treating liquids applied to the thread-helix advancing on the heated reel advantageously may be delivered at about room temperature at the rate of 15 to 100 cc. per minute from each delivery tube; the size of the orifices for the diversion of steam and steam condensate may range from about 3 inch to inch depending upon the location thereof and upon the total number thereof in the steam chamber of the reel; the above factors in turn being adjusted so that a major portion of the steam introduced into the reel is condensed on the thread-helix and before it contacts the threadhelix. Thus by adjusting one or more of these factors, higher or lower thread treating temperatures may be achieved and greater or lesser quantities of condensate may be produced on and within the helix so as to provide whatever volume of condensate-wash is necessary to perform the amount of washing or diluting action desired.

The internal construction of the reels l6 or I! is generally shown in Figure 2 of the drawing. As there shown, such a thread-advancing reel 16 advantageously comprisestwo reel members 36 and 3'! each having a periphery of a plurality of longitudinally extending bar members 39 and 40 respectively. The bar members of the one are interleaved with those of the other. Reel member 36 is secured to the tubular shaft 30 and sealed thereto by means of fluid tight seals 44 and 41 positioned in the end enclosing sections 43 and 46. The seals 44, 41 are drawn fluid tight by the stud 48 turned into a thread bore in the solid front section 45 of the tubular shaft 30. The rear seal 41 is compressed against the shaft by being forced against a collar 50 which abuts a shoulder 51 on the tubular shaft 30 and the front seal 44 is compressed against the shaft by the collar 49. i

The reel member 31 also comprises a plurality of longitudinally extending bar members 40 which interdigitate with the bar members 390i the reel member 36. The bar members 40 at their rearward portions merge into the flange 54 which i is secured to the reel member .31 supporting flange 55 by means of studs 56. The supporting flange 55 is adapted to rotate on spacedbearings 51 (only one set being, shown) positioned about a sleeve 58 having an oifset and askew axis relative to the reel shaft. The reel member 36, because it is secured to the shaft 30, drives the reel member 31. The driving, however, is through the gear 60 that is attached tothe end closure 45 by thstuds 5|. The gear Wis in mesh with an annular gear '62 that is attached to the supporting flange 55 also by means of studs 64.

The hollow shaft 30 serves as a conduit for the steam. The steam flows from the shaft within the reel through openings into a chamber-42 infthe reel member. "Passages H are provided in the peripheral walls of reel member 36 for the flow of steam condensate and steam to the thread members 'on the reel surface. The passages 1| are bored of any desired size so that all of the steam introduced into the reel flows through them as condensate and steam. The passages H open into the spaces betweenthe bar members of the reel member 36 which spaces are occupied by the interdigitating bar members 40. Steam at a desired line pressure up to about 5 pounds is forced into the reel chamber 42 where at least a major portion condenses because of heat given up both to the reel and to the yarn and treating liquids thereon. In this manner a sufficient amount of condensate is provided for the various aqueous treatments of the thread passing over the reel.

Where a chemical treatment is performed on the thread-helix at the take-up or flange end of a thread-advancing reel and a subsequent Wash treatment of the thread-helix is desired, then condensate passages may advantageously be positioned in that part of the reel selected as the washing zone. If a flow of the condensate is desired over a greater number of thread turns, then a plurality of parallel circumferential openings can be provided so as to spread the condensate over a larger area. i There is shown in Figure 3 the heated processing reel I! having heated-fluid passages 83 in the forward or thread discharge end of the heating chamber 8 I. The reel member 80 containing the heating chamber 8|, and the reel member 82 are similar in construction and function to the reel 36, 31 comprising reel l6 of Figure 2. The following examples are more specifically illustrative of preferred methods for treating thread with heated aqueous liquids while such thread is being stored and advanced on steam heated processingreels. 1

Example I A thread formed of 150 denier. 40 filament viscose rayon is produced as follows. A viscose spinning solution containing about 6.5% sodium hydroxide and about 8% cellulose is prepared in the conventional manner. Upon being ripened to an index of approximately 4.5 (sodium chloride) the viscose is extruded through spinneret ll positioned in thecoagulating bath I0, bath I0 being maintained at about approximately 45 C.

and containing approximately, byweight, 12%

' entrained bath liquid.

sulfuric acid, 22% sodium sulfate, 2% zinc sulfate, and 0.1% of a cation-active agent.

The spinning solution is extruded into this bath and the newly formed yarn i 4 is drawn from about 90 meters per minute by means .of the reel 15 on which the thread is stored and advanced while containing The thread [2, while still 1 in an incompletely regenerated state and while wet with the acidb'ath liquidlis then transferred from the reel 15 to reel 16 to which steam is meteredat about 4 pounds per hour. All of the reels I5, I 6, I! and i8 employed in this example are tilted upwardly about 5 at their unsupported ends.

The reel 16, asshown in Figure 2 of the drawing, is providedwith openings ll of about inches diameter between each pair of bars and located at substantiallythe flange or the supported end of the reel. The reel IBis driven at a peripheral speed of about 108 meters per minute so as to stretch thethread about 20% between "reels l5 and 16.. The threadis initially:.wound on the reel .ata pointvahead of the openings 1|,

so as to subject this. portion of 'thehelix: to the washing section. of ..the. condensate and steam As examples of the halites may be mentioned chlorous acids, etc. and the soluble alkali metal and alkaline earth metal salts thereof. Typical of these metal salts are sodium or potassium chlorite. For example, aqueous chlorite solutions having a pH less than about 9 and preferably between about 1 and 8 may be employed with advantage. They may have an available chlorine content between about 0.005% and 0.3% and pref erably between 0.05 and 0.1%.

In practicing the present invention it is found advantageous to incorporate various surface-active compounds together with oleaginous materials into one or more of the aqueous treating liquids present on the heated thread-helix. This practice is found to be effective in scouring and removing sulfur impurities and by-products from the thread undergoing regeneration and washing. Particularly advantageous results are obtained where such compounds are incorporated into a washing medium and near-boiling treatment temperatures are employed. The presence of such compounds may also be effective in maintaining the advancing device free of harmful incrustations. Such surface-active compounds may be cationic, anionic, or even non-ionogenic in character. They may, for example, consist of sulfonated aryl, long chain alkyl, or combination alkylaryl substituted compounds; solubilized amines or amides containing aryl or long chain alkyl radicals; highly polymerized ethylene oxide or long chain hydrocarbons modified with polyethylene oxide radicals, etc. It was found particularly advantageous to incorporate relatively small amounts of oleaginous materials with or without surface-active agents into the steam which is introduced into the thread-advancing reels. In this manner the oleaginous material becomes dispersed in the steam and condensate and is thereafter also diverted to the exterior reel surface and thread-helix.

If desired, the surface-active compounds may be employed to disperse or emulsify various thread lubricants or other oleaginous materials in the aqueous liquids applied to the advancing thread. The thread lubricants may, for example, consist of mineral, vegetable or animal waxes and oils. Concentrations of the order of 0.01% to 4%, by weight, or greater of the lubricant in water may be employed with advantage.

I claim:

1. In the continuous aftertreatment of viscose rayon thread including the step where the thread is heated while being advanced in the form of a helix by circulating steam therethrough the further treatment during this processing step comprising, continually heating the said helix while simultaneously substantially condensing the circulating steam inside the said helix, meanwhile continuously applying a treating liquid to a portion of said helix, continuously immediately radially passing said condensate as a wash to a subsequent portion of the said same helix.

2. In the continuous aftertreatment of viscose rayon thread of claim 1 in which the applied treating liquid is an acid regenerating liquid.

3. In the continous aftertreatment of viscose rayon thread of claim 1 in which the applied treating liquid is an aqueous bleaching solution.

4. In the continuous aftertreatment of viscose rayon thread of claim 1 in which the applied treating liquid is an aqueous desulphurizing liquid.

KENNETH M. MoLELLAN.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,145,281 Walters Jan. 31, 1939 2,326,150 MacLaurin et a1. Aug. 10, 1943 2,393,595 Dawson Jan. 29, 1946 2,468,081 Koster Apr. 26, 1949 2,533,103 Givens et a1. Dec. 5, 1950 OTHER REFERENCES Chemical Engineering, November 1947, page 103, 

1. IN THE CONTINUOUS AFTERTREATMENT OF VISCOSE RAYON THREAD INCLUDING THE STEP WHERE THE THREAD IS HEATED WHILE BEING ADVANCED IN THE FORM OF A HELIX BY CIRCULATING STEAM THERETHROUGH THE FURTHER TREATMENT DURING THIS PROCESSING STEP COMPRISING, CONTINUALLY HEATING THE SAID HELIX WHILE SIMULTANEOUSLY SUBSTANTIALLY CONDENSING THE CIRCULATING STEAM INSIDE THE SAID HELIX, MEANWHILE CONTINUOUSLY APPLYING A TREATING LIQUID TO A PORTION OF SAID HELIX, CONTINUOUSLY IMMEDIATELY RA- 